The role of food allergy in atopic dermatitis.

Atopic dermatitis (AD) affects ∼10% of children. Food allergy is a known provoking cause of AD in a subset of affected children. A literature search of PubMed and Medline was conducted to review the epidemiology and pathophysiology of AD, with special focus on the role of food allergy in the development of AD, its management, and its long-term preventive strategies. A literature search of PubMed and Medline was conducted. Food allergens readily provoke AD in ∼35% of patients, as proven through double-blind placebo-controlled food challenge studies. Milk, egg, wheat, soy, and peanut account for 75% of the cases of food-induced AD. However, the positive predictive values of the parental history, skin-prick tests, or serum tests for detecting food-specific IgE are low, making these unsuitable for use as single diagnostic modalities. Therefore, the use of a food challenge test is very helpful in objectively confirming the history or positive tests. Elimination diets are often helpful in challenge-proven cases, but care must be taken to evaluate the nutritional status of the child. There are few effective long-term strategies to prevent the development of food allergen-induced AD. Early onset of AD has been shown to be a risk factor for the development of other allergic diseases, including other food allergy/sensitization, as part of the atopic march. Treatment of other causes of AD, such as barrier dysfunction and cutaneous infection, are of equal importance to food allergen avoidance. Food allergy is an important provoking cause of AD, but it is only relevant in ∼35% of affected individuals.